Entry dispersion analysis for the genesis sample return capsule

Genesis will be the first mission to return samples from beyond the Earth-m oon system. The spacecraft will be inserted into a halo orbit about the sun -Earth collinear libration point L-1 located between the sun and Earth, whe re it will remain for 2 gears collecting solar wind particles. Upon Earth r eturn, the sample return capsule, which is passively controlled, will desce nd under parachute to Utah. Analysis of the entry, descent, and landing sce nario of the returning sample capsule is described. In particular, the use of gyroscopic stiffness to suppress aerodynamic instabilities is presented. The robustness of the overall entry sequence is assessed through a Monte C arlo dispersion analysis, where the impact of off-nominal conditions is asc ertained. The dispersion results indicate that the capsule attitude excursi ons near peak heating and drogue chute deployment are within Genesis missio n limits. Additionally, the size of the resulting 3-sigma landing ellipse i s 47.8 km in downrange by 15.2 km in cross-range, which is within the Utah Test and Training Range boundaries.